The [jQuery doc for getJSON][1] says it takes a url as an argument. (First hit with "jquery getJSON" search using Google). The [flask doc for url_for][2] (first hit from internet search for "flask url_for" and searching the document) offers another link for [Quickstart][3]. The (supplied) `search` function shows the pieces in action: function search(query, syncResults, asyncResults) { // get places matching query (asynchronously) var parameters = { q: query }; $.getJSON(Flask.url_for("search"), parameters) .done(function(data, textStatus, jqXHR) { I hope this helps. [1]: http://api.jquery.com/jquery.getjson/ [2]: http://flask.pocoo.org/docs/0.12/api/ [3]: http://flask.pocoo.org/docs/0.12/quickstart/#url-building